[LayoutNG] Fix incorrectly positioned empty blocks inside of new BFC

third_party/WebKit/Source/core/layout/ng/ng_units.h

Index: third_party/WebKit/Source/core/layout/ng/ng_units.h
diff --git a/third_party/WebKit/Source/core/layout/ng/ng_units.h b/third_party/WebKit/Source/core/layout/ng/ng_units.h
index 109e2dd6c8db1c4400cb60f4e5401708b417d9ae..cc2dd519e79b0b39d596cef20880d906a27c1e7a 100644
--- a/third_party/WebKit/Source/core/layout/ng/ng_units.h
+++ b/third_party/WebKit/Source/core/layout/ng/ng_units.h
@@ -100,7 +100,7 @@ CORE_EXPORT inline std::ostream& operator<<(std::ostream& os,
 
 // NGPhysicalOffset is the position of a rect (typically a fragment) relative to
 // its parent rect in the physical coordinate system.
-struct NGPhysicalOffset {
+struct CORE_EXPORT NGPhysicalOffset {
   NGPhysicalOffset() {}
   NGPhysicalOffset(LayoutUnit left, LayoutUnit top) : left(left), top(top) {}
 
@@ -113,6 +113,8 @@ struct NGPhysicalOffset {
   NGPhysicalOffset operator-(const NGPhysicalOffset& other) const;
   NGPhysicalOffset& operator-=(const NGPhysicalOffset& other);
 
+  bool operator==(const NGPhysicalOffset& other) const;
+
   String ToString() const {
     return String::format("%dx%d", left.toInt(), top.toInt());
   }